Reverse shoulder arthroplasty for rheumatoid arthritis since the introduction of disease-modifying drugs.

PURPOSE: Rheumatoid arthritis has been associated with poor clinical outcomes in hemiarthroplasty and unconstrained total shoulder arthroplasty. The reverse shoulder arthroplasty can be utilized to address the shortcomings of hemiarthroplasty and unconstrained total shoulder arthroplasty in the inflammatory arthritis patient population. The objective of the present study was to retrospectively review clinical and radiographic outcomes of patients who underwent reverse shoulder arthroplasty for rheumatoid arthritis and other inflammatory arthropathies and provide a comprehensive analysis to identify factors that may alter patient outcomes.
METHODS: We identified 91 primary reverse shoulder arthroplasties performed between 2006 and 2013 in patients with inflammatory arthritis. Seventy-five had at least two years of follow up with an average follow-up of 4.0 years. The average age at the time of surgery was 70 years old. Peri-operative use of steroids, biologics, and methotrexate were reviewed. Outcomes evaluated included revision and reoperation rates, complications, American Shoulder and Elbow Surgeons (ASES) scores, simple shoulder test (SST) scores, component loosening, and scapular notching.
RESULTS: The two and five year implant revision-free survival was 99%. The two and five year re-operation-free survival was 97%. Eighteen (24%) glenoid components required augmentation with corticocancellous autograft from the humeral head. There were two cases of glenoid loosening with gross changes in position. Patients experienced significant pain relief with a 92% satisfaction rate. Shoulder elevation and external rotation improved from 65 and 21 degrees pre-operatively to 138 and 45 degrees post-operatively, respectively (p < .01). Average ASES and SST scores were 72 and 7.0, respectively. The use of prednisone, DMARDs, or biologic medications had no significant impact on outcomes.